1. Field of the Invention
The present invention relates to microwave ovens, and more particularly, to a commercial microwave oven which can dissipate heat from components, effectively.
2. Background of the Related Art
In general, the microwave oven (MWO) cooks food with heat from friction between molecules caused by disturbance of the molecular arrangement of the food made with a microwave (approx. 2,450 MHz). The microwave oven may have one or a plurality of magnetrons.
Microwave oven with one magnetron is employed as domestic use where the microwave oven is not used frequently, and microwave oven with a plurality of magnetrons is employed as commercial use for convenience store and the like where high power is required continuously.
FIGS. 1˜3 illustrate inside structures of related art commercial microwave ovens, schematically.
Referring to FIG. 1, the related art commercial microwave oven is provided with an outer case 11, a base plate 12, an inner case 13, a front panel 14, a rear panel 15, one pair of magnetrons, transformers, and an outfit chamber. An inside space of the inner case is a cooking chamber. The outfit chamber is one side space of an inside space of the microwave oven excluding a part occupied by the inner case, where different components are provided.
During operation of the microwave oven, the magnetrons 17a and 17b and the transformers 16a and 16b generate much heat. Particularly, when the microwave oven is used in a convenience store or the like, it is liable that the magnetrons 17a and 17b are overheated and damaged due to continued use. Therefore, a structure that can cool down the magnetrons 17a and 17b and the transformers 16a and 16b adequately is required.
Referring to FIG. 1, the base plate 12 has a plurality of inlet holes 12a in a front surface for drawing external air, and the rear panel 15 has outlet holes 15a for exhaust of air. FIGS. 2 and 3 illustrate a side view and a rear view of the related art microwave oven, respectively.
Referring to FIGS. 2 and 3, the one pair of transformers 16a and 16b are mounted on one side of the outfit chamber, and the magnetrons 17a and 17b are mounted on a top and a bottom of a rear part of the inner case 13.
The location of the one pair of the magnetrons 17a and 17b far from each other requires a complicated air supply structure for the fan 18a to blow the external air thereto.
That is, a duct 19 is provided for making an air outlet of the fan and the magnetrons 17a and 17b are in communication. Moreover, a centrifugal fan is employed as the fan for drawing external air and blowing the air in a direction perpendicular to an air draw direction. Thus, the external air passes through the fan 18a, flows along the duct 19, and cools the magnetrons 17a and 17b. Then, the air exhausts through the outlet holes 15a in the rear panel 15.
However, the related art microwave oven has the following problems.
First, the occupation of a rear space by the plurality of magnetrons and the duct causes a volume of a rear part of the microwave oven large.
Second, the centrifugal fan as well as the blower motor on the centrifugal fan are expensive.